There is known intake air preheating, cooling and purifying equipment, named accordingly as calorifiers, conditioners, filters, ionisers and ozonators.
From the prior art are known several different technical solutions for conducting outside air into a building's ventilation system through the ground. For example U.S. Pat. No. 5,131,887 discloses an air handling system built into a building's basement, German patent DE-3414973 discloses a system with an air chamber located in the ground, connected with an air intake conduit on top of it, and connected to an air intake conduit of the building.
Document JP2005090929 discloses a ventilating system which performs air supply with ground heat. In the ventilating system air supply to each living room is carried out in such a manner that geothermal air is taken out to a stairwell, stairs, etc., through a pipe installed in a building. The ventilation is carried out with a ventilation fan being attached thereto in a conventional manner. The supply of the ground heat reduces the difference in temperature at the time of ventilation, leading to the reduction in air-conditioning cost.
Document JP2005009737 discloses a system cooling and heating by directly guiding soil heat transferred through a pipe buried under the ground into a room, and efficiently carrying out air conditioning of the room with little energy by using a heating means having an ON/OFF mechanism and using the heat of the heating means in addition to the soil heat during winter. The described system comprises the underground pipe buried in the ground beneath a house, air is sent into the underground pipe by a blower, heat exchange with the heat of soil is carried out in the underground pipe, and the room is air-conditioned by sending air into the room via an air flow passage.
The solution is disclosed by Estonian Utility Model EE-00329-U1, which is geothermal heat exchanger equipment for preheating and cooling of fresh air conducted to living rooms. From the grilled intake opening on the building's façade, fresh intake air is directed into a pressure decreasing chamber located in the ground or under the building's basement floor. From the pressure decreasing chamber, air is conveyed through a conduit into the second pressure decreasing chamber. The outlet of the second pressure decreasing chamber is connected to the building's ventilation system.
More similar to this invention is the design of geothermal heat exchanger equipment disclosed by the inventor of this invention in Estonian patent application P200200212 and Finnish patent application F120040429, which is also a prototype of this invention.